1. Field of the Invention
The present invention relates to a configuration of a microwave oven and, more particularly, to a configuration of an oven cavity of a microwave oven including an uneven bottom wall for purposes of assuring uniform heating.
2. Description of the Prior Art
Well known Microwave Ovens comprise, with reference to FIG. 1, an oven cavity 1, a turntable 2, a magnetron 3, a wave guide 4, a strut 5, two supporting rollers 6, and a driving roller 7. The turntable 2 is provided for carrying a food. The wave guide 4 functions to transfer microwave energy from the magnetron 3 into the oven cavity 1 while microwave heating operations are being carried out in the conventional microwave oven. The turntable 2 is positioned on the strut 5, two supporting rollers 6, and the driving roller 7. The strut 5 and two supporting rollers 6 are provided for only supporting the turntable 2 at the positions thereof while the driving roller 7 serves to rotate and support the turntable 2.
A bottom wall 1a of the oven cavity has a configuration, as best shown in FIG. 2, where a circular recess 1a--a lower than the plane of the bottom wall 1a is provided. The left half of FIG. 2 depicts a cross-sectional view of the bottom wall 1a while the right half illustrates a plane view of the same. The strut 5, the supporting rollers 6, and the driving roller 7 are all arranged within the area of the lower circular recess 1a--a, whereby the upper surface of the turntable 2 is at the same level as the plane of the remaining portion of the bottom wall 1a except for the circular recess 1a--a.
This configuration is to minimize a space reguirement within the oven cavity 1 irrespective of the presence of the turntable 2. However, because of the uniformity of the surface of the circular recess 1a--a, the distance between the bottom wall 1a and the food positioned on the turntable 2 is unvaried while the turntable 2 is driven for cooking purposes. The food is thus overheated in one region and underheated in other regions. Therefore, uniform heating operations can not be expected for the food positioned on the turntable 2.